1. Field of the Invention
The present invention relates to a method and mechanical locking device suitable for securing the closure position of an overhead door having hinged panels carried on rollers that are guided along a pair of channeled roller tracks.
2. Description of Related Art
Portal closures such as overhead opening doors of the type typically used for residential garages and commercial vehicle stalls generally comprise a plurality of horizontal panels that are hinged together along adjacent panel edges for articulation about parallel axes. Each panel is supported at opposite horizontal ends by rollers confined within a channeled track.
Numerous locking appliances for overhead opening doors of the type described rely on direct or indirect radio-controlled electrical or electronic actuation and are subject to compromise with sophisticated radio communication methods. U.S. Pat. Nos. 4,668,899 and 4,819,379 provide examples of this category of locking systems. Mechanical locks having manually sliding deadbolts that may be emplaced on the interior of the overhead door are also available in many designs. U.S. Pat. Nos. 4,031,719 and 5,458,383 describe mechanical locks suitable for the exterior side of overhead garage doors.
A suitable mechanical locking appliance designed for use with a traditional padlock and for placement on the interior side of the door has not been available heretofore. Such a device would be immune to those methods employed to defeat electrically or electronically actuated locks. Emplacement of the lock on the interior side of the door would protect the lock from physical tampering and compromise—the invader would have to break and enter the building via another entryway before he could attack such a garage door lock.
A type of locking appliance that takes advantage of mechanical design features that are widely used in overhead door systems is desirable. Further to this, it is desirable that such a locking device should require only minimum mechanical installation preparation and be suitable for widely used overhead door systems. A locking device that relies on commonly available padlocks combined with a unique, robust and easy-to-use mechanical appliance is also desirable. Finally, the locking device should be simple and easy-to-manufacture and thus available at relatively low cost.